Student Guide
Module 12
Skills, Schedules, and Automation
Claude goes from a tool you open to a system that works on its own. Skills are reusable instruction sets. Schedules trigger them automatically. A weekly sales report that builds itself every Friday at 4 PM.
Charter Oak Strategic Partners · Claude Mastery Program
- What a SKILL.md file is — a system prompt that does a job
- How to build a skill from scratch using Cowork
- How cron expressions schedule recurring tasks
- How to calculate aggregate time savings for your team
Skills: System Prompts with a Purpose
A skill is a SKILL.md file: a reusable set of instructions that Claude follows when activated. Think of it as a standard operating procedure that Claude executes rather than a human. You learned to write system prompts in Module 05. A skill is a system prompt that does a job.
| Section | What It Defines |
|---|---|
| What it does | The task the skill performs |
| Activation | When Claude should use this skill |
| Inputs | What data or files the skill needs |
| Output format | How the result should look and where to save it |
| Constraints | Rules and limitations to follow |
Schedules: Cron Expressions
A cron expression is a single line of text that tells Claude when to run a skill. Five fields: minute, hour, day of month, month, day of week. You do not need to memorize the syntax. You need to know the common patterns:
| Expression | Meaning | Use Case |
|---|---|---|
| 0 9 * * * | Every day at 9 AM | Morning briefing, inbox summary |
| 0 9 * * 1-5 | Weekdays at 9 AM | Daily data quality check |
| 0 16 * * 5 | Every Friday at 4 PM | Weekly sales report |
| 0 0 1 * * | 1st of every month | Monthly summary, reconciliation |
The Weekly Sales Report Generator reads the latest CSV, calculates key metrics, compares to last week, writes a narrative summary, and saves the report. Scheduled for every Friday at 4 PM. The report appears without anyone opening Claude.
Exercise: Build and Schedule a Skill
Instructions: Pick a recurring task you do at least once a week.
- Build a skill for it in Cowork (15 minutes)
- Write the cron expression (5 minutes)
- Test it by running it once (5 minutes)
- Present: what you built, when it runs, how much time it saves per month (2 minutes)
Rule: Build the 80% case first. Get it working. Add complexity later. A simple skill that works is worth more than a sophisticated skill that does not.
The Math
If fifteen people each build a skill that saves two hours per week: 30 hours/week. 1,560 hours/year. At $50/hour fully loaded: $78,000 in recovered capacity. From one training session. From one exercise.
Those are the numbers that justify this program to leadership.
Skills
SKILL.md files: reusable instruction sets. A system prompt that does a job.
Schedules
Cron expressions trigger skills automatically. Five fields: minute, hour, day, month, weekday.
The Combination
Skills define what Claude does. Schedules define when. Together: work happens without you.